When doing spatial selections, you traditionally have options like Intersect, Contains, Boundary touches, and many, many more. But some times that is just not enough... You need that special relation, that ESRI apparently haven’t thought about.
In these cases, we used to have 'The Relation spatial relationship' to handle the situation. 'The Relation spatial relationship' is ESRI's name for what is also known as DE-9IM (ref. 1) and have been included in Arc Desktop as resent as ArcMap 10.8 (ref. 2) But it has disappeared with the introduction of ArcGIS Pro? My national ESRI reseller confirms this, but I have not seen any reply from ESRI Int.
I would like to suggest that 'The Relation spatial relationship' gets re-introduced, in all situations in ArcGIS Pro where you can select options like Intersect, Contains, Boundary touches, etc. It was one of your strongest tools, and we think it's cool.
Here are a few examples (ref.2.) of increasingly advanced stuff, that can be done with 'The Relation spatial relationship'.
Please ESRI - Give us 'The Relation spatial relationship' back!
ref.1: DE-9IM - Wikipedia
ref.2: Types of spatial relationships that can be validated—Help | Documentation